Conventionally, there is known a hybrid laser processing apparatus comprising: an injection nozzle including an injection hole; liquid supply means for supplying the relevent injection nozzle with high-pressure liquid; a laser oscillator oscillating a laser beam; and a condensing lens condensing the laser beam oscillated from the laser oscillator to inject the liquid supplied from the liquid supplying means in a shape of a liquid column from the injection holes to outside and to guide a laser beam to the liquid column with a condensing lens to carry out processing on the object to be processed.
As such a hybrid laser processing apparatus, there is known the one that is provided with a nozzle block including a nozzle passage formed at a tip of a processing head to inject a liquid column and a focus lens focusing a laser beam onto an entrance orifice of the above described nozzle passage to, thereby, guide the laser beam to the liquid column injected from the nozzle passage (Patent Document 1).
In addition, as another hybrid laser processing apparatus, there is known the one including a cylindrical plane and a conical plane being formed to reduce diameters toward an object to be processed inside the processing head so that water is injected from the tip of the cylindrical plane in a shape of a column and those conical plane and cylindrical plane reflect a laser beam to, thereby, guide a laser beam to the injected water (Patent Document 2).    Patent Document 1: National Publication of International Patent Application No. H10-500903    Patent Document 2: Japanese Patent Laid-Open No. 2001-321977